Despite national trends showing declines in violent crime, studies show that violence remains alarmingly high in some communities as well as in homes, schools, and the media. The goal of this proposed R21 project is twofold: To develop a multi-informant, multi-method assessment of youths'exposure to violence in the social environment, anchored to youths'mental health;and to set a foundation for launching new research into the reduction and prevention of the deleterious mental health consequences of youth violence exposure. Our novel approach to assessment is driven by a four-dimensional conception of violence exposure based on the context (setting), content (impact), channel (mode of exposure), and chronicity (frequency of exposure) of specific acts of violence. Our measurement is tied to a comprehensive assessment of mental health (externalizing, internalizing, and traumatic stress disorders) to provide an overall assessment of the burden of violence exposure based on current theory in developmental psychopathology. This investigation will be conducted in socio-economically distressed urban neighborhoods comprising a range of projected risk for exposure to violence in a major metropolitan area of the Northeast. Our study population will be families with children between the ages of 11 and 14 inclusive;we will sample caregiver-youth pairs (dyadic N = 200) for a comprehensive protocol integrating information from the pairs directly with information from data sources across all levels of the social ecology. Our investigation is guided by five aims: 1) Develop and implement a cross-informant, mixed-method protocol for assessing youths'exposure to violence in the social environment;2) Utilize our novel four-dimensional conception of violence exposure to evaluate the psychometric properties of the new individualized protocol and establish internal validity;3) Apply a dual pathway model of how exposure to violence affects mental health outcomes to evaluate the criterion validity of the new protocol;4) Employ multivariate modeling to analyze patterns of exposure and associated outcomes across meaningful subpopulations (e.g., low and high risk for exposure) to assess the generalizability of the new protocol;and 5) Analyze various combinations of reports in order to finalize a protocol for field testing in clinical research settings. Our investigation will provide information critical to understanding how violence exposure leads to negative health outcomes. Ultimately this knowledge will be essential to efforts at reducing the negative impact of exposure to violence. Our approach to measuring youths'exposure to violence is essential for formulating individualized assessment and intervention strategies for ameliorating the negative sequelae of exposure among children and adolescents. Further, the proposed investigation represents a necessary step in expanding our knowledge of how violence in the social ecology impacts individual mental health via biopsychosocial mechanisms. PUBLIC HEALTH RELEVANCE: Although a large body of research confirms detrimental effects of youths'exposure to violence in multiple social contexts on their mental health status, there have been no systematic efforts to develop a theoretically informed measure of exposure to violence across settings. Properly assessing exposure to violence along key dimensions including context as well as severity, frequency, and mode of exposure is an essential step in advancing our understanding of how violence affects youths'mental health outcomes. Better measurement of exposure also will translate into more precise and ultimately more effective intervention strategies. The proposed project aims to develop a new protocol for assessing youths'exposure to violence and exploring how different profiles of exposure account for different patterns of psychopathology.